采用静水溶出率的方法,在25℃、40℃、60℃、70℃、80℃和100℃条件下,探讨了控释肥料中养分累积释放率与温度的变化规律,以期建立控释肥料肥效期或养分释放期的快速预测方法.结果表明,从低温到高温的各种温度处理下,Scotta公司的Osmocote热固性树脂包膜控释肥料养分累积释放曲线都呈二次曲线,相关指数R2均大于0.996.温度与包膜控释肥料肥效期间呈极显著的负相关,并符合一元二次方程,相关指数R2大于0.993.在高温下培养3或8 h建立的预测预报回归方程,可以快速而准确地预测预报包膜控释肥料在常温下(25℃)的肥效期,预测值与实测值只相差2.4 d;而习惯上的微分溶出率法却相差29~42 d.表明用高温下的肥效期预测预报回归法可以在数小时内准确、迅速地预测控释肥料的肥效期.同时该方法可作为控释肥料在线生产质量控制和市场上控释肥料质量检验的候选方法.
Pattern of accumulative nutrients release rate tested at 25℃, 40℃, 60℃, 70℃, 80℃ and 100℃ longevity of CRF by use of regression equation. Results from coated controlled release fertilizer(CRF), Osmocote, was respectively to study and establish a quick method to predict showed that the pattern of accumulative nutrients release curve would fit one factor quadric regression equation at each given temperatures, and all of R2 was bigger than 0. 996. There was a significant negative correlation between temperature and the longevity of the CRF, which the one factor quadric regression equation could also be used to describe the relationship, and its R2 was greater than 0.993. The regression equa- tion between temperature and the longevity could be applied to predict longevity of CRF within a relatively short period of 3 to 8 hours. Based on this one variable factor quadric regression equation the longevity of CRF could be quickly and precisely predicted, and the difference of longevity between the measured and the predicted one is only 2.4 days. However, the difference of longevity between measured and predicted by use of widely or commonly applied method of differential release rate is 29 to 42 days. It could be concluded that the one variable factor quadric regression equation method is more superior to the commonly used one of differential release rate. Longevity of coated CRF could be quickly and precisely predicted in a few hours by application of one factor quadric regression equation method. This method could also be applied to quality control of coated controlled release fertilizer production online and to test CRF quality in the fertilizer market.